train has 26 distinct synonyms spread across 13 of its 17 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
create by training and teaching
“The old master is training world-class violinists”
undergo training or instruction in preparation for a particular role, function, or profession
“She is training to be a teacher”
develop (a child's or animal's) behavior by instruction and practice; especially to teach self-control
“Parents must discipline their children”
exercise in order to prepare for an event or competition
“She is training for the Olympics”
public transport provided by a line of railway cars coupled together and drawn by a locomotive
“express trains don't stop at Princeton Junction”
a procession (of wagons or mules or camels) traveling together in single file
“we were part of a caravan of almost a thousand camels”
a series of consequences wrought by an event
“it led to a train of disasters”
piece of cloth forming the long back section of a gown that is drawn along the floor
“the bride's train was carried by her two young nephews”
wheelwork consisting of a connected set of rotating gears by which force is transmitted or motion or torque is changed
“the fool got his tie caught in the geartrain”
Synonyms, antonyms and the broader and narrower relations for train come from Princeton University’s WordNet. Full sources and licences.